Field emission display and method for fabricating the same

• US 20010004979A1
• Filed: 12/12/2000
• Published: 06/28/2001
• Est. Priority Date: 12/14/1999
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Kim, Sang Mun, Han, Si Wook
• Granted Patent: US 6,741,026 B2
• Time in Patent Office: Days
• US Class Current: 216/4
• CPC Class Codes: B82Y 10/00 Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: C03C 17/36 at least one coating being a metal
• CPC Class Codes: C03C 17/3652 the coating stack containing at least one sacrificial layer to protect the metal from oxidation
• CPC Class Codes: C03C 17/3671 specially adapted for use as electrodes
• CPC Class Codes: C03C 2218/33 by etching
• CPC Class Codes: D01F 9/127 by thermal decomposition of hydrocarbon gases or vapours or other carbon-containing compounds in the form of gas or vapour, e.g. carbon monoxide, alcohols
• CPC Class Codes: H01J 2201/30469 Carbon nanotubes (CNTs)
• CPC Class Codes: H01J 3/022 with microengineered cathode, e.g. Spindt-type
• CPC Class Codes: H01J 9/025 of field emission cathodes
• CPC Class Codes: Y10S 977/952 Display

Abstract

Field emission display and method for fabricating the same, the field emission display including a cathode array having a cathode electrode formed on a substrate, insulating layers and carbon nanotube films for use as emitter electrodes formed alternately on the cathode electrode, and a gate electrode formed on the insulating layer, thereby permitting fabrication of a large sized cathode plate at a low cost because the film is formed by screen printing and exposure, which can reduce the cumbersome steps in fabrication of the related art Spindt emitter tip, and both a low voltage and a high voltage FEDs because the carbon nanotube film used as the emitter has a low work function, with an easy and stable electron emission capability.

Claims

1. A field emission display comprising a cathode array, the cathode array including:

a cathode electrode formed on a substrate;

insulating layers and carbon nanotube films for use as emitter electrodes formed alternately on the cathode electrode; and

,

a gate electrode formed on the insulating layer.

2. A field emission display as claimed in

claim 1

, wherein the insulating layer is a coat of glass paste containing photoresist with a thickness of 0.5˜

50 μ

m.

3. A field emission display as claimed in

claim 1

, wherein the gate electrode is a coat of metal sol solution with a 10˜

200Å

grain size containing photoresist.

4. A field emission display as claimed in

claim 3

, wherein the gate electrode is formed of at least one of Cr, Ni, Mo, Cu, Pt, Ag.

5. A field emission display as claimed in

claim 3

, wherein the gate electrode has a film thickness of 1000˜

10,000Å

.

6. A field emission display as claimed in

claim 1

, wherein the carbon nanotube film is formed by chemical vapor deposition by using a microwave in a range of 2˜

5 GHz.

7. A field emission display as claimed in

claim 1

, wherein the carbon nanotube film has a thickness of 0.5˜

50 μ

m.

8. A method for fabricating a field emission display, comprising the steps of:

(1) forming a cathode electrode, an insulating layer, and a gate electrode on a substrate in succession;

(2) etching the gate electrode and the insulating layer into a cathode array pattern, to form an emitter region;

(3) forming a sacrificial layer on the gate electrode which is not etched;

(4) depositing a carbon nanotube film on the cathode electrode in the emitter region, to form an emitter; and

,

5) etching the sacrificial layer for removing the carbon nanotube formed on the sacrificial layer, to form a cathode array.

9. A method as claimed in

claim 8

, further comprising the step of attaching and bonding the cathode array on the anode substrate having fluorescent material coated thereon with a desired gap provided between the cathode array and the anode substrate by using a spacer, after step (5).

10. A method as claimed in

claim 8

, wherein the substep of forming the insulating film in the step (1) includes the steps of;

screen printing glass paste containing photoresist on the cathode electrode, and patterning the glass paste by exposure and development, and

heat treating the glass paste in a furnace in a mixture atmosphere of at least one of nitrogen, argon, hydrogen, or in a vacuum chamber.

11. A method as claimed in

claim 8

, wherein the substep of forming the gate electrode in the step (1) includes the steps of;

coating metal sol solution with a grain size 10˜

200Å

containing photoresist on the insulating layer, exposing and developing the metal sol, and

heat treating the metal sol in a furnace in a mixture atmosphere of at least one of nitrogen, and argon, or in a vacuum chamber, at 200˜

500°

C.

12. A method as claimed in

claim 8

, wherein the step (4) includes the step of;

chemical vapor depositing the carbon nanotube film in the emitter region by using a microwave with a 2˜

5 GHz wavelength.

13. A method as claimed in

claim 8

, wherein the step (4) includes the step of using vaporized gas having argon or methane mixed therewith.

14. A method for fabricating a field emission display, comprising the steps of:

(1) forming a cathode electrode, an insulating layer, a gate electrode, and a sacrificial layer on a substrate in succession;

(2) etching the sacrificial layer, the gate electrode, and the insulating layer into a cathode array pattern, to form an emitter region;

(3) forming a carbon nanotube film as an emitter on the cathode electrode in an etched emitter region; and

,

(4) etching the sacrificial layer not etched in the step (2) for removing the carbon nanotube formed on the sacrificial layer, to form a cathode array.

15. A method as claimed in

claim 14

, further comprising the step of attaching and bonding the cathode array on the anode substrate having fluorescent material coated thereon with a desired gap provided between the cathode array and the anode substrate by using a spacer, after step (4).